The background of the embodiments involves manufacture of high energy density batteries. More specifically, high energy density batteries manufactured from nanocomposite materials. In addition, the background of the embodiments involves manufacture of high energy density and high specific energy batteries. More specifically, high energy density batteries manufactured from nanocomposite structures and the packaging of these structures into useable battery packs.
As the demand for newer and better portable power sources has increased in recent years, viable alternatives to conventional battery construction have been an increasingly important area of research. Conventional batteries that have been on the market are limited by several factors, one of the most important being the tradeoff between the size of the battery compared to the amount of power that is capable of being delivered. Factors affecting the overall viability of commercial batteries include inefficient use of the material volume, limited active area at the electrode surfaces, low mechanical and thermal compliance for a high stress environments, low charge/discharge rate, and low shelf life due to excess leakage current.
The problem often encountered is that small changes in the structure of battery geometry can produce dramatic effects on top-level performance. “Tab effects,” for instance, arise when the physical proximity of the positive and negative terminals are not carefully considered. If the terminals are too close, the current density inside the battery is too highly concentrated, giving rise to overheating issues and “hot-spots” (See FIG. 1). If large portions of volume inside the battery are not conducting current, the battery loses energy density, and the cost of the materials needed to produce the battery outweighs the decreased economic viability of the product. The electrical performance consequences of these phenomena are manifested in compromised power output.
If current collectors are too far apart, again, energy density is compromised. This time, the separation of charge between the terminals is increased, giving rise to lower ion conduction, and therefore, lower power delivery. Lower total power delivery decreases the usefulness of the battery, and despite the gains in safety due to decreased risk of hot spots, the economic viability of the battery is compromised.